Development and validation of a primary sclerosing cholangitis-specific health-related quality of life instrument: CLDQ-PSC

Objectives: To understand the full impact of primary sclerosing cholangitis (PSC) on patients' health, it is important to assess their health-related quality of life (HRQL). Using the Chronic Liver Disease Questionnaire (CLDQ), we aimed to develop and validate a PSC-specific HRQL instrument. Methods: Previously collected clinical and patient-reported outcome data from PSC patients were used. The original CLDQ with 29 items was subjected to item reduction, followed by factor analysis. A standard HRQL instrument validation pipeline was then applied to the new CLDQ-PSC. Results: There were 100 PSC patients (44 +/- 13 y, 32% male, 79% college educated, 39% cirrhosis, 67% inflammatory bowel disease, 66% ulcerative colitis, and 50% on ursodeoxycholic acid After item reduction and exploratory factor analysis, there were 24 items and 5 factors left; based on factor loadings, the factors were named emotional function, fatigue, symptoms, worry, and sleep. Internal consistency assessment returned Cronbach alpha 0.85-0.94, item-to-own domain correlations > 0.66 for 22/24 items. Known-groups validity suggests discrimination between PSC patients with and without cirrhosis or its complications, obesity, history of depression, weight loss, and PSC patients on versus not on ursodeoxycholic acid (p < 0.05 for all or select CLDQ-PSC domains). Relevant items of Short Form-36 and CLDQ-PSC were highly correlated (all p < 0.0001). Matching with items of another PSC-specific instrument (PSC-patient-reported outcome; 42 items) for relevance and redundancy suggests that CLDQ-PSC is a relevant, comprehensive, and short HRQL instrument, which can be used for patients with PSC. Conclusions: The CLDQ-PSC is a PSC-specific HRQL instrument that was developed using an established methodology and demonstrated good psychometric characteristics.

Automated summary

To fully understand the impact of PSC on patients' health, it is important to assess their HRQL. This study developed and validated a PSC-specific HRQL instrument using the CLDQ. The CLDQ-PSC showed good psychometric characteristics and can be used for patients with PSC.